This is the Park Tool SW-0 3.2mm Spoke Wrench. Professional quality, precision-sized spoke wrenches are hardened and nickel plated for long service. Park Tool Spoke Wrenches are vinyl coated in one of five colors indicating the size at a glance.

SW-0 is sized for 0.127" (3.23mm) nipples and fits the common Edco, Wheelsmith and DT square nipples, among others.